High-concentration mixer for producing a cellulose suspension having a high cellulose concentration

A high-concentration mixer for producing a homogeneous suspension of cellulose in an aqueous solution of a tertiary amine oxide, comprising a stationary container and an agitator arranged in a container axis, wherein the agitator is connected to a motor via a flange provided in the region of the container bottom, and the motor is designed for rotationally driving the agitator for mixing the suspension provided in the container,

• wherein the agitator has at least one helical coil which brings about a vertical downward flow of the suspension in the center of the container and a vertical upward flow of the suspension in the region of the container wall, and
• wherein the flange comprises at least one blade provided on and extending radially beyond its circumference, wherein said at least one blade is designed for wiping the suspension from the container and for supporting the vertical upward flow of the suspension in the region of the container wall, and a spacer is provided between the container bottom and the flange, wherein the spacer ensures a gap of a substantially consistent width between the container bottom and the flange.